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CEREBROVASCULAR DISEASES for medical students. FAWAZ AL-HUSSAIN FRCPC, MPH Assistant Professor Stroke Neurologist. Anatomy:. Intracranial cerebro-vascular system. Circle of Willis: variants. ACA & PCA. MCA. MCA. Common acute stroke presentation based on arterial distribution:. ACA
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CEREBROVASCULAR DISEASESfor medical students FAWAZ AL-HUSSAIN FRCPC, MPH Assistant Professor Stroke Neurologist
Common acute stroke presentation based on arterial distribution: • ACA • MCA M1 Supperior M2 Inferior M2 • PCA • Basilar • Sup. Cerebellar artery • Wallenberg (lateral medulary syndrome) AND • 5 Kinds of lacunar strokes (motor, motor & sensory, sensory, ataxic hemiparesis, and dysarthria-clumbsy hand syndrome)
Features suggestive of brainstem stroke • Vertigo • Diplopia/ dysconjugate gaze, ocular palsy homonymous hemianopsia • Sensorimotor deficits - Ipsilateral face and contralaterallimbs(crossing sign) • Dysarthria • Ataxia • Sudden LOC
Stroke Risk Factors • Age • Male gender • Family History • Genetic causes • Congenital abnormality like in heart or AVM in CNS • Hyper-coagulopathies • HTN • Diabetes • Hyperlipidemia • Atrial Fibrillation • Carotid artery disease • Physical inactivity • Obstructive sleep apnea • Smoking • Substance abuse • Medications • Dissection AND MANY OTHERS,,,,,,,,,,,,,,,,
Stroke Types Ischemic Hemorrhagic Epidural Subdural Subarachnoid Intra-cerebral Intra-ventricular • Thrombosis • Embolism • Lacunar • Hypo-perfusion Venous • Venous sinus thrombosis • Cortical vein thrombosis
Stroke Epidemiology • About 30-40K new cases annually • Lacunar strokes makes near 50 % because of prevalent diabetes • Increasing prevalence of stroke in young because of increasing HTN, diabetes, & substance abuse added to cardiogenic causes (MCC) and hypercoagulopathies • Although stroke incidence is higher in men, women have equal life time risk because they live longer • Stroke is a preventable & predictable disease never use the word: ACCIDENT
Case-1 • 62 yr old man presented to ER because of slurred speech and mild weakness in Rt face and arm lasted about 30 minutes then resolved spontaneously. His neurological exam at ER was unremarkable. Q-1: What is the most likely diagnosis? And would CT(brain) result matters?? Q-2: How would you manage such patient?
TIA • 2002 definition: A brief episode of neurological dysfunction caused by focal brain or retinal ischemia, with clinical symptoms typically lasting <1 hr, and without evidence of acute infarction • 20% of TIA pts will have stroke within 3 months ALARM FOR COMING STROKE
Case-2 • A 67 yr old lady brought to ER because of sudden difficulty in talking, and weakness in Rt face , arm, and leg without sensory deficit. Questions: ~ What is difference between slurred speech and aphasia? ~ Is there any clinical scale can be used to determine the severity of the stroke? ~ What is most likely affected artery? ~ No headache; so it must be an ischemic stroke ! ~ When can I treat with thrombolysis using IV-tPA?
Case-2 • A 67 yr old lady brought to ER because of sudden difficulty in talking, and weakness in Rt face , arm, and leg without sensory deficit. Questions: ~ What is difference between slurred speech and aphasia? Mechanical vs content ~ Is there any clinical scale can be used to determine the severity of the stroke? NIHSS ~ What is most likely affected artery? Lt MCA ~ No headache; it must be an ischemic stroke! NO ~ When can I treat with thrombolysis using IV-tPA?
Pre Hospital Mx: Guidelines for EMS Management of Patients with Suspected Stroke: • Manage ABCs • Cardiac monitoring • Intravenous access • Oxygen (keep O2 sat >92%) • Assess for hypoglycemia • NPO • Alert receiving ED • Rapid transport to closest appropriate facility capable of treating acute stroke Not Recommended: • Dextrose-containing fluids in non-hypoglycemic patients • Excessive blood pressure reduction • Excessive IV fluids
Acute Ischemic Stroke Work-up • Detailed and accurate history is ESSENTIAL At ER • CBC, lytes, Cr, and coagulation profile • 12 leads ECG, and troponin • CT (brain)… mainly to R/O hemorrhage • Then acute stroke Rx if met indications and no contraindication but needs approval from pt or his family
Acute stroke imaging: • Hypo-attenuation of brain tissues • Loss of sulcal efffacement • Insular ribbon sign • Obscuration of lentiform nucleus • Hyperdense sign (MCA>basilar>PCA)
Acute Stroke Treatment Options • IV t-PA • IA t-PA • IV t-PA followed by IA t-PA • Endovascular & mechanical disruption
Acute Ischemic stroke treatment using IV t-PA • Only TPA approved for ischemic stroke if given within 4.5 hours of stroke onset • Target: salvage the penumbra tissues (at risk) • 30 % more likely to have minimal or no disability at 3 months ( NINDS trial) • 6.4% vs. 0.6% increase in the frequency of all symptomatic hemorrhage • IA t-PA in selected cases
Acute Ischemic stroke treatment using IV t-PA Contraindications: B.P. > 185/110 Acute MI Recent hemorrhage LP within 7 days Arterial puncture at incompressible site Surgery within 14 days Bleeding diathesis Head trauma within 3 months History of intracranial hemorrhage Minor or rapidly improving stroke symptoms
THROMBOLYTICS: IV-TPA Original NINDS trial: • Absolute difference in favorable outcome of tPA versus placebo was 11-13% across the scales • Depending upon the scale, the increase in relative frequency of favorable outcome in patients receiving tPA ranged from 33% to 55%. • The effect of tPA was independent of stroke subtype, with beneficial effects seen in those with small vessel occlusive, large vessel occlusive and cardio-embolic induced ischemia.
IV –tPA side effects • 6% develop symptomatic intracerebral hemorrhage within 36 hours following treatment (0.6% in placebo group). • Half of the tPA associated symptomatic hemorrhages were fatal, however tPA treatment was not associated with an increase in mortality in the three-month outcome analysis. Facial angioedema : another side effect which may cause airway obstruction.
THROMBOLYTICS: IA-TPA IA thrombolysis is an option for treatment of selected patients who have major stroke of <6 hours’ duration due to occlusion of MCA, and who are not otherwise candidates for IV-TPA. IA thrombolysis is reasonable in patients who have contraindication to use of IV-TPA, such as recent surgery (new recommendation). Txrequires pt to be at experienced stroke center with immediate access to cerebral angiography and qualified interventionalists (new recommendation).
Mechanical Disruption: MERCI device is reasonable intervention for extraction of intra-arterial thrombi in carefully selected patients, but panel recognizes that utility of device in improving outcomes after stroke is unclear (new recommendation).
Anticoagulation in Acute Stroke !! Urgent anticoagulation with goal of preventing early recurrent stroke, halting neurological worsening, or improving outcomes after acute ischemic stroke not recommended. Urgent anticoagulation not recommended for pts with moderate to severe strokes because of increased risk of serious ICH complications. Initiation of anticoagulant tx within 24 hours of IV-TPA not recommended.
Antiplatelet Rx: Class I recommendation: 1. Oral administration of ASA 325 mg within 24 to 48 hours after stroke onset is recommended for tx of most pts.
BP management: • For IV-tPA: follow NINDS guidelines 185/110 • Not candidate for thrombolysis: 220/120 • Use Labetalol IV 10 mg Q 30 min. PRN • Avoid quick reduction in BP and look for bradycardia. • Alternative: Hydralazine IV • Avoid strong vasodialtors
Stroke Work-up (after acute stroke Mx) • Fasting blood glucose and lipid profile • Carotid U/S in all pts • Echocardiogram/ 24 hr holter monitor to R/O paroxysmal At.Fib for pts with embolic stroke In selected cases: • MRI/MRA brain • CT angio (extrcranial and intracranial BVs) • Screen for hyper-coagulopathies • Many other tests to identify the cause and then improve the secondary prevention strategy each patient is different
Secondary stroke prevention • Antiplatelet therapy (aspirin, dipyridamole, or plavix) • Combined antiplatelet Rx …. In special scenarios • Statin….. Keep LDL cholesterol 1.3 – 2 • Antocoagulation for At.Fib or hypercoagulopathy • Avoid unnecessary anticoagulation • Carotid artery surgery (CEA or stent) • Many uncommon causes of stroke exist and each require special approach and wt benefits vs risks. Therefore; secondary stroke prevention is better done at specialized stroke prevention clinics run by stroke experts
Post stroke care: • Maximize secondary stroke prevention • Rehabilitation (motor, language, behavioral,…) • Special care for swallowing and DVT prophylaxis • Most limiting factors for rehab are: 1) Vascular dementia 2) Extensive large stroke • Prognosis: Without thrombolysis: 10% die, 30% mild, 30% moderate, and 30% severe disability With thrombolysis: 9% die, and 30% more chance of complete recovery (great Rx but not perfect)
Intracranial Hemorrhage Common causes • Hypertension • Trauma • Amyloidangiopathy. • Ruptured vascular malformation. • Coagulopathy (a disease or drug-induced) • Hemorrhage into a tumor . • Venous infarction. • Drug abuse.
HTN- Induced IC hge • Can be putaminal, thalamic, cerebellar, or lobar. • Can be seen in acute HTN or chronic one • Can be fatal
Subarachnoid Hge • Worst headache ever • Use: H&H scale • Spont. Vs. traumatic • Risk of aneurysms increase with smoking (X40 times) • Sacularanurysms are more in anterior circulation (90%) while fusiform more in basilar • 1st & 4th tubes of CSF for cells • Need conventional angiogram and neurosurgery consultation for clipping or coiling